Applicability of thermography for cancer diagnosis in small animals.

Medical thermography is an imaging test used to monitor skin surface temperature. Although it is not a recent technique, significant advances have been made since the 2000s with the equipment modernization, leading to its popularization. In cancer diagnosis, the application of thermography is supported by the difference in thermal distribution between neoplastic processes and adjacent healthy tissue. The mechanisms involved in heat production by cancer cells include neoangiogenesis, increased metabolic rate, vasodilation, and the release of nitric oxide and pro-inflammatory substances. Currently, thermography has been widely studied in humans as a screening tool for skin and breast cancer, with positive results. In veterinary medicine, the technique has shown promise and has been described for skin and soft tissue tumors in felines, mammary gland tumors, osteosarcoma, mast cell tumors, and perianal tumors in dogs. This review discusses the fundamentals of the technique, monitoring conditions, and the role of thermography as a complementary diagnostic tool for cancer in veterinary medicine, as well as future perspectives for improvement.

Imatinib Mesylate for the Treatment of Canine Mast Cell Tumors: Assessment of the Response and Adverse Events in Comparison with the Conventional Therapy with Vinblastine and Prednisone.

Mast cell tumors (MCTs) are common neoplasms in dogs, and treatments for these diseases include surgery, polychemotherapy and targeted therapy with tyrosine kinase inhibitors. This study aimed to evaluate the response and the adverse events of treatment with imatinib mesylate (IM) compared to conventional therapy using vinblastine and prednisolone (VP) in canine cutaneous MCTs. Twenty-four dogs were included in the study; 13 animals were treated with IM and 11 with VP. Tumor tissue samples were submitted for histological diagnosis, grading and KIT immunostaining. The response to treatment was assessed by tomographic measurements according to VCOG criteria. Adverse events were classified according to VCOG-CTCAE criteria. The IM and VP groups had dogs with similar breeds, gender, ages, MCT localization, WHO stages and lymph node metastasis profiles. Most MCTs were grade 2/low and had KIT- patterns 2 and 3. The objective response rate (ORR) was significantly higher (30.79%) in the IM group then in VP group (9.09%). Adverse events (AE) in IM group were all grade 1, significantly different from VP. In conclusion, IM presented better ORR and less severe adverse events when compared to VP, representing a suitable option for the treatment of low-grade canine MCTs.

Photodynamic therapy and diagnosis: Principles and comparative aspects.

Photodynamic therapy (PDT) is an evolving method of treating superficial tumours that is non-invasive and carries minimal risk of toxicity. It combines tumour-selective photosensitiser dyes, tissue oxygen and targeted illumination to generate cytotoxic reactive oxygen species (ROS) within the tumour. In addition to directly acting on tumour cells, PDT damages and restricts tumour microvasculature, and causes a local inflammatory response that stimulates an immune response against the tumour. Unlike surgery or radiotherapy, the surrounding extracellular matrix is unaffected by PDT; thus, tissue healing is excellent and PDT seldom causes scars. This, combined with the ease of light application, has made PDT a popular treatment for cancers and pre-cancerous conditions in human beings. Moreover, because photosensitiser dyes are fluorescent and selectively accumulate in tumour tissues, they can additionally be used to visualise and discriminate tumour from normal tissues, thereby improving the accuracy of tumour surgery. In veterinary practice, PDT has been used successfully for treatment of superficial squamous cell carcinomas of the feline nasal planum; urinary tract, urinary bladder and prostate neoplasia in dogs; and equine sarcoids. The purpose of this article is to provide a comparative review of the current literature on PDT in human and veterinary medicine, and to establish a basis for future development of PDT in veterinary medicine.

Serum and plasma vascular endothelial growth factor in healthy dogs / Fator de crescimento do endotélio vascular no soro e plasma de cães saudáveis

Vascular endothelial growth factor (VEGF) is an angiogenic factor with a key role in physiological and pathological process. It can be measured in several organic fluids, including serum and plasma samples. The aim of this work was to investigate the concentration of serum and plasma VEGF of healthy dogs in order to recommend optimal handling of biological samples for accurate measurement of VEGF. Blood samples of thirty dogs were collected into sterile EDTA tube for plasma analysis and into clot activator tubes for serum analysis. The tubes were centrifuged within 90 minutes of collection at 1400 xg for 10 minutes. VEGF concentration was determined using the quantitative method (ELISA). Serum VEGF level was 26.5 + 13.3pg/mL and plasma VEGF was 11.7 + 16.4 pg/mL (p = 0.0003). There was a positive correlation between serum VEGF and platelets (r = 0.37, p = 0.03) and a negative correlation between serum VEGF and hemoglobin (r = -0.38, p = 0.03) and between plasma VEGF and  hemoglobin (r = -0.34, p = 0.06). When compared with serum samples it was concluded that plasma samples could be used as an optimal fluid for measuring VEGF in dogs.

O fator de crescimento do endotélio vascular (VEGF) é um fator angiogênico com papel importante em processos patológicos e fisiológicos. O VEGF pode ser quantificado em diversos fluidos orgânicos, incluindo amostras de soro e plasma. O presente trabalho investigou a concentração do VEGF no soro e no plasma de cães saudáveis a fim de recomendar o manejo ótimo de amostras biológicas para a determinação dos níveis do VEGF. Amostras de sangue de 30 cães saudáveis foram coletadas em tubos estéreis contendo EDTA para análise do plasma e em tubos com ativador de coagulação para análise do soro. Os tubos foram centrifugados após 90 minutos da coleta a 1.400 x g por 10 minutos. A concentração do VEGF foi determinada com o método quantitativo de ELISA. O nível sérico médio de VEGF foi de 26,5+13,3pg/mL e o plasmático foi 11,7 + 16.4 pg/mL (p = 0,0003). Houve correlação positiva entre o VEGF do soro com as plaquetas (r = 0,37, p = 0,03) e correlação negativa entre o VEGF do soro com hemoglobina (r = -0,38, p = 0,03) e entre VEGF do plasma com hemoglobina (r = -0,34, p = 0,06). A comparação dos resultado obtidos nos exames de plasma e soro indicou que amostras de plasma podem ser utilizadas como ótimo fluido para quantificação do VEGF de cães.

Vascular endothelial growth factor expression and microvascular density in soft tissue sarcomas in dogs.

The aim of the current study was to evaluate the expression of vascular endothelial growth factor (VEGF) and the microvascular density in canine soft-tissue sarcomas. Immunohistochemistry for VEGF expression was performed on 20 canine neoplasms by the streptavidin-biotin-peroxidase method using an anti-VEGF mouse monoclonal antibody (ab-119). The volume fraction of microvessels in the sarcomas was quantified in hematoxylin and eosin-stained tissue sections. At least 10 fields of view (40x magnification) per neoplasm were analyzed by positioning a grid with 100 points and counting the microvessels that fell into the intersection points. This percentage was considered the volume fraction of these microvessels in the tumor section. VEGF expression was detected in 65% of the neoplasms. In 92.3% of the neoplasms, the expression occurred in the peritumor region; in 46.15%, in the intratumor region; and in 38.46%, the expression was present in both regions. The cells responsible for VEGF expression were fibroblasts and macrophages in the peritumor region or in the pseudocapsule and neoplastic cells in the intratumor region. Greater intratumoral VEGF was expressed in hemangiopericytomas (P = 0.04). No difference was present in the volume fraction of tumor microvessels between VEGF-positive and VEGF-negative neoplasms (P = 0.3416) or for the different types of neoplasms (P = 0.5). The results of this study suggest that VEGF participates in the angiogenesis of soft-tissue sarcoma in dogs. Additional research will be necessary to elucidate the contribution of VEGF to the progression of malignancy.

Biópsia hepática por laparotomia paracostal em bovinos e búfalos / Paracostal liver biopsy in cattle and buffalo

A técnica de biópsia hepática em ruminantes tem importante valor no diagnóstico clínico de doenças tóxicas e metabólicas, em especial nos desequilíbrios minerais. As técnicas mais comumente utilizadas restringem análises devido ao limitado volume de tecido obtido. No presente trabalho, avaliou-se o uso de uma técnica de biópsia hepática por laparotomia paracostal em bovinos e búfalos. Foram utilizados 10 bovinos e 10 búfalos hígidos. Os animais foram mantidos em estação, sedados com xilazina e infiltrados localmente com lidocaína e epinefrina. O acesso à cavidade abdominal foi realizado por meio de uma incisão dorso-ventral de 15cm no flanco direito, iniciada ventralmente (cerca de 4-5cm) ao processo transverso da 2a ou 3a vértebra lombar e situada caudalmente (cerca de 4cm) e paralelamente à 13a costela, obtendo-se visualização do fígado. Foi então realizado pinçamento do bordo caudal do órgão com pinça Doyen para remoção de fragmento hepático (2 a 4g). Procedeu-se o fechamento da cavidade abdominal como de rotina. Foram analisados os parâmetros bioquímicos e hematológicos antes do procedimento (tempo zero) e após 24 horas, 48 horas, 5 dias e 10 dias após a biópsia. Todas as variáveis bioquímicas estudadas retornaram aos valores basais 5 e 10 dias após o procedimento nos bovinos e búfalos, respectivamente. O tempo médio de cirurgia por animal foi de 25 minutos. A biópsia hepática por laparotomia paracostal demonstrou ser uma técnica eficaz e de baixo risco à saúde dos animais, permitindo a coleta de suficiente quantidade de tecido hepática para realização de múltiplas análises.

Liver biopsy in ruminants is an important technique for clinical diagnosis of toxic and metabolic diseases, especially mineral disorders. The most frequent procedures used so far results in an small amount of liver and not enough for multiple tests. The present study aims to evaluate the efficacy of paracostal laparotomy liver biopsy technique in cattle and buffalo and to follow possible changes on biochemical and hematological profiles caused by the surgery. Ten cattle and ten buffalo were used in this study. The animals were kept on their normal position and sedated with xilazin and locally infiltrated with lidocain and epinefrin. The access to abdominal cavity was carried through a right paracoastal laparotomy, ventrally to the transverse process of 2nd or 3rd lombar vertebra. A small portion of the hepatic caudal lobe (2 to 4g) was clinched by a Doyen clamp and removed. The abdominal cavity was closed as normally routine. Blood samples were taken to biochemical tests and hemogram before the procedure, and 24h, 48h, 5 and 10 days later. The technique was practical and easy to be performed (took approximately 25 minutes). The technique described here was efficient and offers low risk to animal health and provided enough amount of liver tissue for multiple tests.

Clinical study of cryosurgery efficacy in the treatment of skin and subcutaneous tumors in dogs and cats.

OBJECTIVE: To evaluate the efficacy of cryosurgery for treatment of skin and subcutaneous tumors in dogs and cats. STUDY DESIGN: Prospective study. ANIMALS: Dogs (n=20), cats (10). METHODS: Cutaneous or subcutaneous tumors were treated by liquid nitrogen cryosurgical spray (1 cm from target tissue at 90 degrees until a 5-mm halo of frozen tissue was achieved) for 15-60 seconds. Malignant lesions had 3 freeze-thaw cycles benign tumors, 2 cycles. The second or third freeze cycle was performed after complete thaw of the preceding freeze. Wounds healed by second intention. Follow-up was weekly for 1 month and then twice monthly until wounds healed, and final outcome was determined by telephone interview of owners. RESULTS: Tumor size ranged from 0.3 to 11 cm diameter with 28 (60%) being 0.3-1 cm; 8 (17%) 1.1-3 cm, and 11 (23%) >3.4 cm. Complications included edema, erythema and for extremity lesions, pain and lameness. Treated lesions (n=47) had an overall remission of 98% (mean follow-up, 345+/-172.02 days [range, 150-750 days]). One malignant peripheral nerve sheath tumor recurred 7 months after cryosurgical treatment. CONCLUSION: Cryosurgery is an efficient method for treatment of skin and subcutaneous tumors in dogs and cats. CLINICAL RELEVANCE: Cryosurgical ablation is an effective means of treating small cutaneous or subcutaneous tumors in dogs and cats, especially in older animals where wound closure or cosmetic outcome might limit surgical excision alone.